#include <stdio.h>

int main(void) {
int aa;
int ab[100]={1};
int ac=1;

scanf("%d",&aa);
do{
ab[ac]=ab[ac-1]*2;
ac++;
}while(ab[ac-1]<=aa);
ac=ac-2;
if(aa!=ab[ac])ac=ac+1;
printf("%d",ac);
	return 0;
}